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71.
72.
K. M. Garg 《Acta Mathematica Hungarica》1963,14(1-2):187-195
73.
Ratios of coincidence counting rates of annihilation gammas at 0 and 10m rad were measured for 16 atomic percentages of indium
in liquid mercury. Theory of trapping of positrons at solute atoms and solute-vacancy complexes is applied. Complete angular
correlation measurements for 14.3, 25, 35, and 50 atomic percentages of indium were also made and showed possible effects
of solute-vacancy complexes on the smearing of the angular correlation distributions. 相似文献
74.
75.
M.A.G. Soler G.B. Alcantara W.R. Viali J.R.L. Fernandez V.K. Garg P.C. Morais 《Surface science》2007,601(18):3921-3925
In this study γ-Fe2O3 nanoparticle, surface-coated with increasing amount of oleic acid, have been prepared while the stability against particle degradation under laser excitation intensity was investigated. Maghemite nanoparticle was obtained via oxidation of magnetite nanoparticle, the latter synthesized by co-precipitation of Fe (II) and Fe (III) ions in alkaline medium. By varying the experimental conditions of surface-coating maghemite nanoparticles with oleic acid, samples with different grafting coefficient were obtained and investigated using X-ray diffraction and different spectroscopic techniques, namely Raman, Mössbauer, and infrared. The amount of oleic acid adsorbed on the maghemite surface was estimated via the carbon content obtained from elemental analysis. 相似文献
76.
Recent X-ray diffraction studies on α-quartz (SiO2) by Kingmaet al [1], have shown the occurrence of a reversible, crystalline-to-crystalline, phase transition just prior to amorphization
at ≈ 21 GPa. This precursor transition has also been confirmed by our recent molecular dynamics simulation study [2]. In order
to investigate the possibility of a similar behaviour in other isostructural compounds, which also undergo pressure induced
amorphization, α-GeO2 and α-AlPO4 (berlinite form) were studied using energy dispersive X-ray diffraction. In either of these materials, no such phase transition
is detected prior to amorphization. The onset of amorphization and its reversal is found to be time dependent in GeO2. 相似文献
77.
78.
A simple spectrophotometric method applicable to waste water bodies is developed for the determination of anionic surfactant (AS). An ion‐association complex is formed between an anionic surfactant Sodium dodecyl sulphate (SDS) and a cationic dye Crystal Violet (CV). The dark blue colored complex can be easily extracted in organic solvent benzene. The absorbance of the complex in benzene layer is measured spectrophotometrically at maximum wave length (λ max) of 565 nm. Under the optimal experimental conditions, absorbance of the organic extractant obeyed Beer's law over the range of 0.75–10.00 μg mL?1 of SDS and the LOD was 0.01312 μg L?1. It is noticed that the present method is much easier, less time consuming and applicable to accelerated urbanization and industrial development found in newly formed Chhattisgarh state in Central India. The validity of the method was tested in regionalized industrial and domestic waste water runoff. 相似文献
79.
80.
A method to study domain structure in ferroelectrics, using pyroelectric effect is described. Variation of pyroelectric signal
from the surface of a triglycine sulphate crystal plate has been studied by scanning the surface of the crystal with a low
wattage He-Ne laser beam. The integrated pyroelectric signal is due to two components, namely, (1) the primary component arising
out of the change in spontaneous polarization with temperature and (2) the delayed component arising out of the possible polarization
reversal. The component of an electric field along the ferroelectric axis due to thermal hemisphere within the crystal plate
formed by the laser beam has been calculated and shown to exceed coercive field, making polarization reversal possible. The
delayed pyroelectric signal is a measure of polarization reversal within the patch illuminated and its observed variation
over the surface yields information of the domain structure. 相似文献